Question

The total number of cyclic structural isomers of $C_6{H}_{12}$ are:

• A. 10
• B. 12
• C. 14
• D. 16

Answer 1

The correct option is B 12

For a compound with molecular formula $C_c{H}_h{X}_x{N}_n{O}_o$

$\text{Degree of unsaturation}=(c+1)-\frac{h}{2}-\frac{x}{2}+\frac{n}{2}$

Molecular formula of the given compound is $C_4{H}_6$
$\text{Degree of unsaturation}=(6+1)-\frac{12}{2}=1$

Thus, it should have one ring structure in the molecule.
Thus, the cyclic isomers are 12.